oma-backend

oma-backend is a skill for Claude Code, Codex from first-fluke/oh-my-agent. It costs 41 tokens per session (2,141 once invoked), scanned C, original, MIT.

A backend development guide for server-side applications, including APIs, databases, authentication, business logic, and background jobs. It organizes work into routers, services, repositories, and data models.

In plain words
What is it for?
Use it to build or review REST or GraphQL endpoints, login and access control, database integrations and migrations, server logic, queues, and background jobs.
Why use it?
It helps keep request handling, business rules, data access, validation, and authentication in clear parts of the application.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one. Also seen: installed under .agents/ (shared by several agents).

Part of the oma plugin — 33 skills shipped together , and of oma

Good fit Use it to build or review REST or GraphQL endpoints, login and access control, database integrations and migrations, server logic, queues, and background jobs.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/first-fluke/oh-my-agent/oma-backend
About the project

oh-my-agent is a harness for checking whether coding agents actually completed their work by verifying tests, required artifacts, independent reviews, and recorded decisions. It is used across multiple agent runtimes to make workflow results auditable instead of relying on an agent's own report. The catalogue add-ons provide parts of its skills, agents, hooks, MCP integrations, instructions, and plugins.

first-fluke/oh-my-agent · 1,278 stars · on GitHub · firstfluke.com

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent
npx skills add first-fluke/oh-my-agent --skill oma-backend
Clone the repo
git clone --depth 1 https://github.com/first-fluke/oh-my-agent

Made for: Claude Code, Codex.

Or install oma, the plugin that ships this one along with the rest of its 33 skills.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for oma-backend

README.md
[![agentmods](https://agentmods.dev/badge/skills/first-fluke/oh-my-agent/oma-backend/github.svg)](https://agentmods.dev/skills/first-fluke/oh-my-agent/oma-backend)
Your own site
<a href="https://agentmods.dev/skills/first-fluke/oh-my-agent/oma-backend"><img src="https://agentmods.dev/badge/skills/first-fluke/oh-my-agent/oma-backend/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for oma-backend

Your own site · 80×15
<a href="https://agentmods.dev/skills/first-fluke/oh-my-agent/oma-backend"><img src="https://agentmods.dev/badge/skills/first-fluke/oh-my-agent/oma-backend.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 41 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,141 The whole file, excluding the scripts and references it only reads on demand.
Security scan C 1 finding. A grade says what 26 rules found in the file — not that it is safe. Third-party audits
  • NVIDIA SkillSpector warn 7 Sept 2026
SkillSpector: 7 findings, up to high

These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →

  • high YARA Match · line 3
    YARA rule matched a hack tool or exploit indicator (offensive tools, reconnaissance, privilege escalation, or exploit frameworks).
    Fix: Remove offensive tool references and exploit code. Legitimate agent skills should not contain penetration testing tools, exploit frameworks, or reconnaissance utilities.
  • high Prompt Injection · line 42
    Hidden instructions were detected in comments or invisible text. These could contain malicious directives. Manual review is recommended.
    Fix: Audit all comments and invisible characters. Remove any instructions that direct the agent to perform unauthorized actions. Use plain, reviewable content.
  • high Prompt Injection · line 108
    Hidden instructions were detected in comments or invisible text. These could contain malicious directives. Manual review is recommended.
    Fix: Audit all comments and invisible characters. Remove any instructions that direct the agent to perform unauthorized actions. Use plain, reviewable content.
  • high Prompt Injection · line 181
    Hidden instructions were detected in comments or invisible text. These could contain malicious directives. Manual review is recommended.
    Fix: Audit all comments and invisible characters. Remove any instructions that direct the agent to perform unauthorized actions. Use plain, reviewable content.
  • high Prompt Injection · line 44
    Hidden instructions were detected in comments or invisible text. These could contain malicious directives. Manual review is recommended.
    Fix: Audit all comments and invisible characters. Remove any instructions that direct the agent to perform unauthorized actions. Use plain, reviewable content.
  • high Prompt Injection · line 110
    Hidden instructions were detected in comments or invisible text. These could contain malicious directives. Manual review is recommended.
    Fix: Audit all comments and invisible characters. Remove any instructions that direct the agent to perform unauthorized actions. Use plain, reviewable content.
  • high Prompt Injection · line 186
    Hidden instructions were detected in comments or invisible text. These could contain malicious directives. Manual review is recommended.
    Fix: Audit all comments and invisible characters. Remove any instructions that direct the agent to perform unauthorized actions. Use plain, reviewable content.
How audits are shown
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00041 $0.02141
Opus 5 $0.00020 $0.01071
Sonnet 5 $0.00008 $0.00428
Haiku 4.5 $0.00004 $0.00214

Measured today against content hash ca48bcff2812, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-09, from the pricing page.

Security

Grade C, and why

oma-backend scanned grade C with 1 finding against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured today.

The scan reads SKILL.md. This mod also ships 2 executable files (variants/node/api-template.ts, variants/python/api-template.py), listed below but not scanned — reading those needs a real analyzer, not pattern matching.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Hidden instructionshighPrompt injection

Directives inside HTML comments, invisible characters or bidirectional overrides are read by the model and not by the person reviewing the file.

<!-- oma-docs:ignore-start -->
Origin

Copies of this mod

2 near-identical copies found in the catalogue:

.agents/skills/oma-backend/SKILL.md · 201 lines

How it starts

The opening of the file, as written. The whole thing — 201 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Backend Agent - API & Server Specialist

Scheduling

Goal

Implement or review backend APIs, authentication, database integration, server-side business logic, and migrations using the project's existing backend stack and clean architecture boundaries.

Intent signature

  • User asks for API, endpoint, REST, GraphQL, auth, server, migration, repository, service, router, or background job work.
  • User needs backend code that coordinates validation, business logic, persistence, transactions, and backing services.

When to use

  • Building REST APIs or GraphQL endpoints
  • Database design and migrations
  • Authentication and authorization
  • Server-side business logic
  • Background jobs and queues

When NOT to use

  • Frontend UI -> use Frontend Agent
  • Mobile-specific code -> use Mobile Agent

Expected inputs

  • Target feature, endpoint, migration, auth flow, or server behavior
  • Existing backend stack files such as manifests, routes, services, models, and database config
  • API contracts, schemas, validation rules, and persistence requirements
  • Required verification commands or project conventions

Expected outputs

  • Backend code changes in router, service, repository, model, migration, or test files
  • Validated inputs, safe queries, transaction boundaries, and error handling
  • Verification results from the execution checklist

Dependencies

  • Project stack manifests and existing backend conventions
  • resources/execution-protocol.md, resources/checklist.md, and resources/orm-reference.md
  • Optional stack/stack.yaml, stack/tech-stack.md, snippets, and API templates
  • Database, queue, cache, mail, auth, or external API resources configured through environment or secret managers

Control-flow features

  • Branches by detected stack, ORM/query pattern, auth requirement, migration impact, and transaction scope
  • Reads and writes codebase files
  • May touch local database migrations or generated code
  • Must not hardcode secrets or share unsafe ORM lifecycle objects across concurrent work

Read the full file on GitHub · 201 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. today Changed · -3 lines ca48bcff2812
  2. 3d ago Changed 0214188cd86c
  3. 10d ago First seen · 204 lines · 41 tokens per session scan C 23a51b126bc1

Subscribe to this mod's changes

oma-backend is a skill published in the GitHub repository first-fluke/oh-my-agent (1,278 stars, last pushed today), licensed MIT. It adds 41 tokens to every session and 2,141 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it C with 1 finding (hidden instructions). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.